Department of Physics & Astronomy
University of New Mexico

Center for Astrophysics Research and Technologies Seminar Series

A-mazing BAaDE's window

Presented by Lorant Sjouwerman (NRAO)

The Bulge Asymmetries and Dynamic Evolution (BAaDE) project has produced the largest-ever survey of red giant SiO maser sources in the Galactic Bulge and Inner Galaxy. The SiO maser transitions at 43 and 86 GHz are not hindered by extinction, and yield extremely accurate stellar line-of-sight velocities. The detection of ~15,000 SiO masers yields numbers comparable to optical surveys, with the additional strength of a much more thorough coverage of the highly obscured Inner Galaxy and Galactic Plane, where Galactic dynamic signatures are most informative. The sample is sufficient to trace complex Galactic structures and minority populations, and yield luminous SiO masers suitable for follow-up orbit and parallax determinations using VLBI. The coverage of multiple SiO, and SiO-isotopologue transitions allow detailed studying of the SiO maser pumping mechanism, including as function of stellar pulsation phase. When distances are obtained, from direct and indirect methods, stellar dynamics of the Galactic gravitational potential and stellar properties such as mass-loss-rate and SiO maser luminosity functions can be derived.

This presentation will introduce the BAaDE survey, summarize the current status, showcase early results, explain current challenges and peek into future developments.

2:00 pm, Thursday, May 11, 2023

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